Hydraulic balancing mechanism

ABSTRACT

The invention provides an hydraulic balancing mechanism whereby elements or bodies may be oscillated to or from a utile and an inutile position and employs an hydraulic cylinder, a piston therein, a chamber above and a chamber below the piston, a spring in the lower chamber contacting the piston and compressible by movement of the cylinder relative to the piston, a bushing slidable in the piston having a bore, a slidable hollow rod carrying the bushing, there being communication between the chambers through said bore, the rod and a lateral opening in the latter, and valve means for said bore of the bushing operably mounted in the hollow of the rod.

l I l l 3 611 3 7 267/128 FllMS/UO 267/113 128,141,71

Avenidn de las Torres 92, Znom 9,

References Cited shdable hollow rod carrylng the bushing, there bemgcommu- UNITED STATES PATENTS nication between the chambers through saidbore, the rod and a lateral opening in the latter, and valve means forsaid bore of the bushing operably mounted in the hollow of the rod.

3,008,746 Senger.........l................ 267/128 PATEHTTU 85? 71971 9I w J 1;,

INVENTOR, time Eva; Her/82 w,

ATTORNEY.

HYDRAULIC BALANCING MECHANISM The instances for use of a hydraulicbalancing mechanism or system are numerous in many cases in whichelements of a certain weight or volume must be oscillated or turned byhand, but vary their operation according to the differences in the sizeor weight of the element, making it necessary to dismantle at least partof the mechanism of the balancing means to adjust same.

Widespread employment of the mechanism or system is in the holding andstorage of disappearing beds, during the day in dwellings. At presentthis is generally attained by using bulky and much maneuverabletransformable furniture, without completely fulfilling the purpose ofreal beds.

Through the instant hydraulic mechanism it is possible to tilt or rock acomplete'bed around an axis located within a wall cavity or equivalent,and swing the bed completelyinto the cavity or similarly mount the bedbetween parallel partitions in a frame or article of furniture, so thatduring daytime the space usually occupied by the bed is completely'freefor other uses. a

The foregoing example does not limit the use of the inven' tion, sinceother examples are the balancingof large gates in manufacturing plants,upwardly swinging doors at garage entrances, rigid shutters to protectthe plate glass of show windows in case of violence as well as manyother no less interesting cases.

In the present invention, hydraulic means have been employed so as tomake the same manually adjustable without the necessity of anydismantling of parts, even during operation. The invention provides apreferably metallic cylinder in which is contained a relatively stronghelicoidal spring, a piston sliding hermetically in said cylinderdefining an upper and lower chamber therein, the upper extremity of saidstrong spring engaging the lower face of said piston, a hermeticallysealed cover for the upper extremity of the cylinder, a straight tubularrod which extends hermetically tight through and slides in said coverinto the upper chamber of the cylinder and slidably into the upperportion of said piston and with the bore of the tubular rod enablingcommunication with the lower chamber of the cylinder. To the interior ofthe lower extremity of said tubular rod, the upper portion of a tubularbushing is attached as by screw threading. The bushing has a borethroughout its length and the upper edge of the bore is a valve seatwhich is approximately level with the upper end of the piston. Saidtubular rod above the location of said valve seat has a small lateralopening 12 which communicates with the upper chamber of the cylinder.The tubular inside or bore of the rod contains a longitudinally movablevalve pin whose lower extremity may be conical and adapted to seathermetically at the adjacent circular edge of the mentioned bushing, andthe upper extremity of which is a stopper.

Said stopper is an enlargement of, rigid, or integral with the pin whichseal hermetically the upper extremity of the bore of the rod. Suchstopper is screwed to the bore wall of the rod and at its outsideextremity the rod at the stopper has a manual means operable to adjustsaid screwing in such a manner that the conical extremity of the rod mayclose by seating at the upper end of the bore of said bushing.

In the accompanying drawing of one example of the invention:

FIG. 11 is a diagrammatic elevational view of a head portion of a bedconcealed in a wall recessed, for example, and its association with thebalancing hydraulic means of this invention;

FIG. 2 is a diagrammatic elevational view of the same parts as FIG. 11in position after the bed has been oscillated to its horizontal or openposition for use, particularly emphasizing the raising of the armjoining it to said balancing hydraulic means; and

FIG. 3 is an enlarged sectional view taken substantially along thelongitudinal axis of the hydraulic cylinder of the balancing means.

In said drawings, FIGS. 1 and 2 illustrate how, in the case of a tiltingbed A pivoted at a and concealed in a vertical position in a recess Bofa wall or equivalently in an article of furniture, for example, thebalancing means at cylinder 1 being con nected by means of arm C hingedat 1b to the bed. In FIG. 2 said arm C has been raised, which raisingalso raises cylinder 1 relatively to its tubular rod 2 hinged at itsupper extremity to a fixed projection 28 on the rear wall or equivalentplace within the recess B.

In FIG. 3, said arm C is rigid, or integral with said cylinder 1, theparts being primarily metallic and the cylinder being closed at itsbase.

The rod 2 is a tubular straight metallic part and its lower extremity,usually interiorally enlarged at 2a, slidably enters into the upper areaof the axial opening or bore 3a of a piston 3. A bushing 4 is carried bytubular rod Z'being screwed at 20 into said enlarged portion2a ofthe'rod 2. Moreover, said piston slides relatively to the unitarytubular rod 2 and'bushing 4 and the bushing 4 carries midway of itsends, a sliding hermetic seal joint 14 which creates between the rod 2,the piston 3 and the bushing 4 a hermetic and united unit.

THe cylindrical outside wall of piston 3" has the necessary circularseal or joint 15 to obtain the tightness which must exist around thepiston to define and maintain the independence of the two chambers D andE within the cylinder, said joint 15 being toric at the same time topermit gentle sliding. Said chamber D preferably contains a suitableliquid.

The cylinder at its upper extremity has a removable cover, or head 5which has a hermetic seal therewith by means of a toric joint 16preferably large, to facilitate its insertion. Through an opening insaid head 5 said rod 2 is slidable and since the latter sliding isfrequent, maximum tightness must be obtained, as by means of a removableflat or skelper bushing 17, a removable double retainer 18 and aremovable elastic ring 19, all composing a unitary removable cylinder,piston and rod of the hydraulic means.

A strong helicoidal, or equivalent, spring 7 is contained in the lowerchamber D of the cylinder ll, resting on the bottom thereof and theupper extremity is in contact with a large disc 6 through which bushing4i slidably passes, bushing 4 is fastened in place by a nut 11 screwedto it. A thin washer, or ring 20 is disposed intermediate the piston 3and disc 6.

When the apparatus such as the bed A is lowered from the position ofFIG. 1 to that of FIG. 2, the element A of the bed movescounterclockwise as shown by the arrow X in FIG. I of the drawing;cylinder 1 is raised by said arm'C resulting in the reduction in thesize of chamber D, the fluid contained in the latter partly displaces orraises through the bore 4a of the bushing 4 from chamber D into the boreof rod 2 at 2a and thence through a lateral hole 12 of rod 2 above theupper face of the piston 3 and into the chamber lE while at the sametime tensioning of the helicoidal spring 7 increases since it iscompressed through the raising of cylinder I. When the bed A is raisedto its stored-away position of FIG. 2 of the drawing, the bed A willmove clockwise as indicated by the arrow Z of FIG. 2 of the drawing.

Under the conditions described, the operation of this hydraulic meansalways has the same resistance under similar circumstances andconditions as occurs in known shock absorber arrangements. In others, itis possible to vary the sec tion of passage of the fluid by placingbefore same an eccentn'c washer whose position is varied bydisassembling the piston.

According to the invention, the variation of the passage for the fluidis obtained by placing inside of the tubular rod 2 an axially movablevalve bar, or pin 10 whose diameter is slightly larger than that of thebore 4a of the bushing 4. Said valve pin at its lower extremity ispreferably conical to coact wit the mouth, or valve seat 4b of saidbushing 45. At its upper extremity, the valve pin is welded to acylindrical plug 8 housed hermetically in an internal enlargement 2d ofthe rod 2. Around this plug, or enlargement 8 are toric hermetic seals21 which permit both axial and longitudinal movement of the pin l0.

Said plug 8, in its upper portion, has a somewhat greater diameter sothat it can better be threaded at 2e in the internal threads with whichrod 2 is equipped. Above said threaded portion 2e, plug 8 has a head 2faccessible so that it may be adjustably turned along with its connectedpin in one direction or the other for the purpose of seating the pin 10at 4!; or spacing it therefrom. ln the present example, said head 2f hasseveral radial holes 8a for tool engagement to exert a tangential forceto the right or to the left.

If the cone of the valve pin 10 engages seat 4b it will close thepassage to the fluid originating from chamber D of the cylinder whensaid chamber is being reduced in size and therefore will prevent thisrelative movement between the cylinder and its rod, and the hinging ofthe elements of the apparatus, or mechanism being operated will beimmobilized. The greater separation, or space between theabove-mentioned seat 41) and the conical extremity of pin 10 the morefluid shall be able to pass during a unit of time and the movement ofthe mechanism shall be obtained more easily. Finally, with a sufficientseparation of said conical extremity above the lateral passage 12 of rod2, this passage is completely free, as if the regulating valve pin 10did not exist.

The upper extremity of tubular rod 2 is detachably and turnably mountedat H as to the arm 28 fastened to a wall within recess B, the structurebeing detailed at the top of FIG. 3. Such tubular rod extends turnablyand detachably into a coupling 29 in which position it is held by splitspring means 22 engaged in grooves 22a of the tubular rod. Near the top,the coupling has two holes in which a cylindrical pivot means 24 isaccommodated, being retained in place as by pins 25. The coupling 29 isopen or has clearance at 26 to permit application and operation of atool to engage one or both of the holes 8a to adjust, or regulate theheight of valve pin 10 relative to seat 4b. The above-mentioned pivotmember 24 is used to hinge the hydraulic means to any adequate support,such as a bifurcation of arm 28.

Piston 3 also has one or more passages 13 therethrough, parallel withthe axis of tubular rod 2, the outlet of which is at the lower face ofthe piston and covered by one or several flexible discs, or membranes, 9which are pressed against said face by a circular spring 27 supported ona shoulder washer, a of disc 6.

After bringing the apparatus, or mechanism which is being operated, toits final position, there is a recovery of the fluid between the twochambers D and E. If the pressure of said fluid is sufficiently strongin the upper chamber to overcome the normal tension of the spring 27upon its bushing by membrane 9, said spring 27 pressing against theshoulder 27a of disc 6 and thus being filtered with more or lessintensity toward said lower chamber furthering the tension of thecompressed spring 7.

lclaim:

1. Apparatus of the class described comprising a cylinder, a pistontherein intermediate the ends thereof providing a first chamber at oneside thereof and a second chamber at the other side thereof, a spring insaid first chamber compressible against said piston to tension itthrough relative movement of the cylinder and piston in one direction, atubular rod axially slidable into one end of said cylinder, said secondchamber and said piston, the bore of said tubular rod above the pistoncommunicating with the second chamber, a single valve means comprising abushing and a valve pin, carried by said tubular rod, said bushingextending through the piston and having a passage therethroughcommunicating with the second chamber by means of the bore of saidtubular rod and having a valve seat, said valve pin being disposedwithin said tubular rod and being rotatively and longitudinally movablerelatively to said rod and to said valve seat to control the passage offluid through the bushing from one chamber to the other chamber.

2. Apparatus according to claim 1 wherein said valve pin is screwthreaded to said tubular rod for adjustment to vary its spacing withrespect to its seat.

3. Apparatus according to claim 1 wherein said bushing 18 screwed tosaid tubular rod and said valve pin is adjustably screw threaded to saidtubular rod.

4. Apparatus according to claim 1 including a coupling to which saidtubular rod is fastened, having clearance at one location, means on saidvalve pin extending into said clearance operable to adjust the positionof the valve pin relatively to the seat, and fixed mounting means forsaid coupling.

5. Apparatus according to claim 1 wherein said piston has a passagetherethrough, a flexible disc means covering said passage, a disc memberon said bushing below said piston, a nut on said piston below said discmember, and an expansive spring mounted on sad disc member varyingagainst said flexible disc.

6. Apparatus according to claim 1 wherein the bore of said rod isenlarged at its upper portion, an enlargement on said rod disposed inthe first-mentioned enlargement, said secondmentioned enlargement beingscrew threaded to the hollow rod, means to movably couple said rod to asupport, and said rod being accessible at its upper end portion foradjustment of the pin valve at screw threads to vary the position of thevalve pin relative to its seat.

1. Apparatus of the class described comprising a cylinder, a pistontherein intermediate the ends thereof providing a first chamber at oneside thereof and a second chamber at the other side thereof, a spring insaid first chamber compressible against said piston to tension itthrough relative movement of the cylinder and piston in one direction, atubular rod axially slidable into one end of said cylinder, said secondchamber and said piston, the bore of said tubular rod above the pistoncommunicating with the second chamber, a single valve means comprising abushing and a valve pin, carried by said tubular rod, said bushingextending through the piston and having a passage therethroughcommunicating with the second chamber by means of the bore of saidtubular rod and having a valve seat, said valve pin being disposedwithin said tubular rod and being rotatively and longitudinally movablerelatively to said rod and to said valve seat to control the passage offluid through the bushing from one chamber to the other chamber. 2.Apparatus according to claim 1 wherein said valve pin is screw threadedto said tubular rod for adjustment to vary its spacing with respect toits seat.
 3. Apparatus according to claim 1 wherein said bushing isscrewed to said tubular rod and said valve pin is adjustably screwthreaded to said tubular rod.
 4. Apparatus according to claim 1including a coupling to which said tubular rod is fastened, havingclearance at one location, means on said valve pin extending into saidclearance operable to adjust the position of the valve pin relatively tothe seat, and fixed mounting means for said coupling.
 5. Apparatusaccording to claim 1 wherein said piston has a passage therethrough, aflexible disc means covering said passage, a disc member on said bushingbelow said piston, a nut on said piston below said disc member, and anexpansive spring mounted on sad disc member varying against saidflexible disc.
 6. Apparatus according to claim 1 wherein the bore ofsaid rod is enlarged at its upper portion, an enlargement on said roddisposed in the first-mentioned enlargement, said second-mentionedenlargement being screw threaded to the hollow rod, means to movablycouple said rod to a support, and said rod being accessible at its upperend portion for adjustment of the pin valve at screw threads to vary theposition of the valve pin relative to its seat.